我正在使用Firebase数据库在应用程序中的两个用户之间挑战。在挑战中，我存储了player1Uid和player2Uid（player1是发起挑战的玩家，第二个玩家是接受或拒绝挑战的玩家）。我想记录挑战的历史记录，因此，如果挑战已完成，则将其存储在名为“ completedChallengesList”的列表中；如果挑战尚未完成，则将其存储在名为“未完成的挑战列表”的列表中。代码有时可以正常工作但是在其他情况下，它会将数据多次带入列表。
这是我带来数据的代码：
public void startAsynkTask() {
//TODO : search for a solution to this error
AsyncTask asyncTask = new AsyncTask() {
@Override
protected Boolean doInBackground(Object[] objects) {
try {
Socket sock = new Socket();
sock.connect(new InetSocketAddress("8.8.8.8", 53), 1500);
sock.close();
return true;
} catch (IOException e) {
return false;
}
}
@Override
protected void onPostExecute(Object o) {
if ((boolean) o) {
clearLists();
ChildEventListener generalChallengesListener = new ChildEventListener() {
@Override
public void onChildAdded(DataSnapshot dataSnapshot, String s) {
String challengeState = dataSnapshot.child("state").getValue().toString();
Log.v("Logging2", "onChildAdded");
if (challengeState.equals(uncompletedChallengeText)) {
getChallengeData(dataSnapshot, "onChildAdded");
view.onDataFound();
}
}
@Override
public void onChildChanged(DataSnapshot dataSnapshot, String s) {
//TODO : note that the only changing handled is when challenge moves from uncompleted to completed state
getChallengeData(dataSnapshot, "onChildChanged");
for (int i = 0; i < uncompletedChallengesList.size(); i++) {
if (uncompletedChallengesList.get(i).getId().equals(dataSnapshot.getKey())) {
uncompletedChallengesList.remove(i);
view.notifyAdapters(completedChallengesList.size(), uncompletedChallengesList.size());
break;
}
}
checkListsSizeAndAdjustViews();
view.hideProgressBar();
}
@Override
public void onChildRemoved(DataSnapshot dataSnapshot) {
startAsynkTask();
}
@Override
public void onChildMoved(DataSnapshot dataSnapshot, String s) {
}
@Override
public void onCancelled(DatabaseError databaseError) {
//Toast.makeText(getActivity(), "فشل تحميل البيانات من فضلك تأكد من الاتصال بالانترنت", Toast.LENGTH_SHORT).show();
view.hideProgressBar();
Log.v("Logging", "error loading data : " + databaseError);
}
};
//this code gives data where current user is player 1
player1Listener = challengesReference.orderByChild("player1Uid").equalTo(currentUserUid).addChildEventListener(generalChallengesListener);
//this code gives data where current user is player 2
player2Listener = challengesReference.orderByChild("player2Uid").equalTo(currentUserUid).addChildEventListener(generalChallengesListener);
challengesReference.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
onInitialDataLoaded();
Log.v("ChallengesFragPresenter", "completed list size :" + completedChallengesList + " , uncompleted list size : " + uncompletedChallengesList);
challengesReference.removeEventListener(this);
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
} else {
view.onNoInternetConnection();
}
}
};
asyncTask.execute();
}
public String getChallengeData(DataSnapshot dataSnapshot, String tag) {
Log.v("ChallengesFragPresenter", "get challenge data called");
Log.v("ChallengesFragPresenter", "completedChallengesList : " + completedChallengesList.size()
+ ", uncompletedChallengesList " + uncompletedChallengesList.size());
view.startCompletedChallengesAdapter(completedChallengesList);
view.startUnCompletedChallengesAdapter(uncompletedChallengesList);
GenericTypeIndicator<List<Question>> t = new GenericTypeIndicator<List<Question>>() {
};
challenge = new Challenge();
String challengeDate = dataSnapshot.child("date").getValue().toString();
String challengeSubject = dataSnapshot.child("subject").getValue().toString();
String challengeState = dataSnapshot.child("state").getValue().toString();
String challengeId = dataSnapshot.getKey();
ArrayList challengeQuestionsList = (ArrayList) dataSnapshot.child("questionsList").getValue(t);
long player1Score = (long) dataSnapshot.child("player1score").getValue();
long player2Score = (long) dataSnapshot.child("player2score").getValue();
String player1Name = dataSnapshot.child("player1Name").getValue().toString();
String player1Image = dataSnapshot.child("player1Image").getValue().toString();
String player1Uid = dataSnapshot.child("player1Uid").getValue().toString();
String player2Name = dataSnapshot.child("player2Name").getValue().toString();
String player2Image = dataSnapshot.child("player2Image").getValue().toString();
String player2Uid = dataSnapshot.child("player2Uid").getValue().toString();
String challengerName, challengerImage;
if (player1Uid.equals(currentUserUid)) {
currentPlayer = 1;
challengerName = player2Name;
challengerImage = player2Image;
challenge.setSecondChallengerUid(player2Uid);//second means that it is not the player who starts the challenge
if (tag.equals("onChildAdded")) {
player1childrenCount++;
}
} else {
currentPlayer = 2;
challengerName = player1Name;
challengerImage = player1Image;
challenge.setSecondChallengerUid(player1Uid);//second means that it is not the player who starts the challenge
if (tag.equals("onChildAdded")) {
player2childrenCount++;
}
}
challenge.setCurrentPlayer(currentPlayer);
challenge.setChallengerName(challengerName);
challenge.setDate(challengeDate);
challenge.setImage(challengerImage);
challenge.setSubject(challengeSubject);
challenge.setState(challengeState);
challenge.setId(challengeId);
challenge.setQuestionsList(challengeQuestionsList);
String score;
if (currentPlayer == 1) {
score = player2Score + " : " + player1Score;
} else {
score = player1Score + " : " + player2Score;
}
challenge.setScore(score);
if (challenge.getState().equals("اكتمل")) {
view.showCompletedChallengesTv();
if(!completedChallengesList.contains(challenge)) {
completedChallengesList.add(0, challenge);
}
view.notifyAdapters(completedChallengesList.size(), uncompletedChallengesList.size());
} else if (challenge.getState().equals(refusedChallengeText)) {
view.showCompletedChallengesTv();
if(!completedChallengesList.contains(challenge)) {
completedChallengesList.add(0, challenge);
}
view.notifyAdapters(completedChallengesList.size(), uncompletedChallengesList.size());
} else if (challenge.getState().equals(uncompletedChallengeText)) {
view.showUncompletedChallengesTv();
if(!uncompletedChallengesList.contains(challenge)) {
uncompletedChallengesList.add(0, challenge);
}
view.notifyAdapters(completedChallengesList.size(), uncompletedChallengesList.size());
}
return player1Uid;
}
经过长时间的调试，我发现添加一个新的子对象时，多次调用getChallengeData（）方法。我做了很多尝试来知道为什么，但是我做不到。
注意：我正在使用asynk任务在开始加载数据之前检查是否存在Internet连接。
答案 0 :(得分：0)
我认为您的问题是，您没有删除列表程序“ generalChallengesListener”，因此将创建多个引用，因此onChildAdded将被多次重复删除，其数量取决于您创建的列表程序的数量。因此，添加对列表器的引用，并知道何时应删除它。 希望对您有帮助=）